Species of Aphytis are among the most important parasitoids of armored scale
insects (Homoptera: Diaspididae). Many of the species used in classical
and augmentative biological control programs around the world, including
type and important voucher material, are represented in collections of
the
University
of
California
, Riverside (UCR).

The UCR collection of Aphytis
formed the basis for a world taxonomic revision of the genus by David
Rosen and Paul De Bach in 1979. The monograph was based almost entirely
on the UCR collection of Aphytis,
and because of this, it is an invaluable resource for basic and applied
scientists. The UCR collection of Aphytis
is almost entirely comprised of reared and slide-mounted specimens
collected from 74 different countries and territories over the last 70
years. The magnitude and scope of the collection make it irreplaceable.
Its revitalization will stabilize the existing collection and hopefully
stimulate additional taxonomic studies of this important genus.

Because of their minute size, these wasps are generally ignored
by collectors and are not accumulated in most insect collections. The
UCR collectionincludes ca.
30,000 specimens of Aphytis
mounted on ca. 5,000 slides. The majority of these specimens (28,224)
are mounted in a temporary, water-soluble medium (Hoyer's) on 4,380
slides. A significant number of these mounts are now in various stages
of decay. Many specimens, including numerous type specimens, have
already been damaged. The purpose of this project is to protect the
collection by transferring a significant portion to Canada balsam, a
permanent medium better suited for preserving specimens in taxonomically
significant collections of micro-Hymenoptera. Specimens are mounted
individually and properly labeled. Currently, the majority of the
material is mounted with an average of 6.67 specimens per slide,
sometimes with more than one species per slide, and labeled very poorly.

REMOUNTING
PROCEDURE

This procedure generally follows the one outlined by Platner et.
al. (1999,) with a few modifications that are better suited for
remounting Aphytis specimens.It
allows specimens originally mounted in Hoyer's medium to be transferred
to Canada balsam with minimal damage.A significant problem in remounting is that the antennae may
collapse after contacting with the balsam.The following method prevents major collapsing in about 90% of
the specimens.The rate of
success in remounting and avoiding possible problems is the initial
quality of the specimens: the better their original condition is, the
fewer problems are encountered during the process of remounting.

The standard remounting procedure is as follows.

1) Coverslips of Hoyer's mounts almost always have been sealed
with Zut® or other compounds to reduce desiccation.This material is removed with the tip of a razor blade before
processing.

2) Slide is placed in a
Petri dish and soaked in distilled water for 60-72 hours.After soaking, the coverslip can be lifted free of the specimen(s).

3) Specimen(s) is/are
transferred with a hooked probe to a ceramic depression plate supplied
with 10% ethanol, then covered with a 6mm coverslip.

4) Ethanol is replaced
with 10% KOH for 30-40 min. (if the specimen is already clear enough) or
up to 24 hours (if the specimen has not been cleared in the original
slide).At this point, the
quality of the original specimen can be improved somewhat.KOH not only is a clearing and softening agent but also reduces
head and antennal collapse.Therefore,
specimens must be treated with KOH even if they had previously been
cleared in the Hoyer's medium.Because
of flattening from the previous mount it is very difficult to reposition
specimens during the remounting process.

5) KOH is removed with
a pipette and replaced with 10% ethanol for 30 min.The dehydration procedure is repeated with 20%, 40%, 60%, 80%,
95%, and twice with 100% ethanol.

6) Absolute ethanol is
replaced with a 1:1 mixture of 100% ethanol and clove oil.The depression plate with specimens is placed into a partly
opened container for 2-3 weeks to allow for slow, complete evaporation
of the alcohol and any remaining water.Once evaporation is complete only clove oil will remain and the
specimen is ready for mounting.

7) Using the balsam
applicator, a small drop of Canada balsam (pre-mixed with 15% clove oil)
is picked and placed in the center of a clean slide, which sits in a
template to assist proper positioning of the specimen at the center of
the slide.A dot of mountant
ca. 3-4 mm in diameter is optimum, but this dot should not be mixed or
spread significantly. The specimen is gently placed in the mountant by
removing it from the clove oil with a hooked probe and submerging it,
dorsum up, in the balsam drop.At
this point the specimen can be oriented and some minor repositioning of
body parts is possible.It
is important to do it quickly, not allowing the mountant to dry after
specimen placement.Dry 6 mm
coverslips (precleaned with 80% ethanol and lens tissue) is then
immediately placed flat, parallel with the slide, on the specimen.This allows it to contact the balsam drop near its center and
forces air bubbles out when pressure is applied with the forceps.

8) The slide is marked
with the individual code to assure proper labeling, and a corresponding
male (M)
or female (V)
symbols is marked on the slide in such a way that they indicate
positioning of the specimen on the slide.The slide is then labeled in such a way that specimen's head is
positioned upside down relative to the label; this is necessary to
assure that when this specimen is viewed using a compound microscope, it
appears in the right position with its head up.

9) The slide(s) is/are
placed onto slide warmer (50°C) for 3-7 days.

LABELING

The original slide (usually without specimens) is kept for
historical purposes and is the main source of labeling information.However, because many slides do not contain proper labeling data,
when possible we compliment the original data with complimentary
information available either from Rosen & De Bach (1979), other
relevant publications, or from the UCR quarantine records.

Labels from the original slide (Fig. 1) are glued to it if
necessary after the specimens are removed from it by soaking it in
distilled water.On top of
the slide, a new label is attached which contains the bar code number(s)
of the slides that contain the specimen(s) remounted from this original
slide.Example: "UCRC
ENT 000151-000166".The
original slides will be stored separately at the end of the Aphytis
collection, arranged numerically, rather than alphabetically, for
easier access.

The
new slide(s) is/are labeled in the following way (Fig. 1).The right label contains locality, date, collector's name, and
other relevant data such as host record(s), plant record(s), P. De
Bach's catalog number, any notes or other codes, etc.The left label indicates the species identification, sex
indication, name of the person responsible for identification and the
date (if available).In the
bottom, the left label states "Remounted from Hoyer's into Canada
balsam 1998 or 1999 by M. Planoutene or V. Berezovskiy (UCR)."

Finally, the bar code with the data-base number is affixed to the
slide between the identification label and the coverslip, as shown in
Fig. 1.

Fig.
1.The syntype slide of Aphytis
melinus DeBach before and after remounting.

DATA-BASING

All label and other relevant data about each specimen remounted
on the new slide is entered into the Biota (Windows-95) data-base.Each slide is given the unique number, which is the same number
as the bar code on the slide.The
bar code number is entered automatically using the Intermec bar code
reader (Model 1550), connected to a Twinhead Slimnote Power Book
(TE-200TZ).The number
appears in the field called "Specimen code".When available, geographical coordinates, host information, etc.
is added to the original label data.

STORAGE

After the remounted slides are dry enough, they are returned in
the proper place in the Aphytis collection.The UCR has 6 wooden cabinets for storing the slides flat; there
is space for permanent storage of all the type and some non-typematerial there.The
rest of the slides, mainly the common species such as Aphytis
melinus De Bach, A.
lingnanensis Compere, etc., will be stored separately in 100-slide
capacity boxes.